Now Arrays:
DC
state[-1] = DC

state[abc] = 5

state["abc"] = 5
state[2.5] = Nevada
state[2.3] = Nevada
state[2] = Nevada
CaliforniaCaliforniaCalifornia
state[4] = Array

Array

Array ( [-1] => DC [2] => Nevada [5] => New York [large] => California [abc] => 5 )